1. Field of the Invention
The present invention relates to a magnetic head having a negative pressure type slider. More particularly, the present invention relates to an improvement in a negative pressure type slider used for a magnetic head.
There has been used a flying type magnetic head for a magnetic disk apparatus for computers. The flying type magnetic head is adapted to read and write data by producing an air bearing function between a magnetic disk and the slider of the magnetic head while they are relatively moved at a high speed. In the magnetic head of this kind, there has been known a spring loading system and a negative pressure system wherein a negative pressure produced at the slider is utilized, as means to ensure a magnetic interface between a magnetic disk and the slider of the magnetic head. The present invention concerns the negative pressure type magnetic head between the above-mentioned two kinds of magnetic head.
A negative pressure type magnetic head is a self-loading type magnetic head which utilizes a negative pressure produced at the slider, which has advantages that it is unnecessary to provide a spring loading mechanism and a low loading operation is allowed. As a conventional technique of the negative pressure type magnetic head, there has been known one disclosed, for instance, in Japanese Unexamined Patent Publication No. 35765/1983 (U.S. Pat. No. 4,420,780). FIG. 11 shows a magnetic head disclosed in the above-mentioned publication, wherein a reference numeral 1 designates a slider and numerals 21, 22 designate reading/writing elements. The slider 1 is composed of ceramics in which two rail portions 101, 102 are provided spaced apart from each other at its one surface and the reading/writing elements 21, 22 are respectively provided at an end portion of the rail portions 101, 102.
Further, a recessed portion 103 as a negative pressure producing area is formed between the rail portions 101, 102. The recessed portion 103 has a bottom surface 104 which terminates at an end 105 of the slider, and which terminates at the other end where a vertical wall surface 106 is formed so that the wall surface 106 sharply rises at an angle of about 90.degree. toward a surface of the slider.
In the negative pressure type magnetic head as shown in FIG. 12, a side of the slider 1 where the reading/writing elements 21, 22 are formed is an air discharging side and the opposite side is an air inflowing side with respect to the air-flowing direction indicated by an arrow mark a. In operations, the slider 1 is attracted toward the magnetic disk 3 by a negative pressure F.sub.1 produced at the recessed portion 103, whereby a small air bearing is formed.
In the magnetic head disclosed in Japanese Unexamined Patent Publication No. 35765/1983, however, the recessed portion 103 had to be formed by ion milling or the like and it was impossible to use a cutting means such as a wire saw, a rotating grindstone or the like because the recessed portion 103 as a negative pressure producing area had a vertical wall surface 106 which sharply rises at an angle of about 90.degree. toward a surface of the slider at the air in-flowing side. Since the slider 1 was composed of ceramics which is difficult to process, it took much time to process the recessed portion of the slider by ion milling. Accordingly, there was a problem that processability was poor, whereby it was unsuitable for a large scale production.